If wrong, a fellow gets punished (5)
I believe the answer is:
fined
'punished' is the definition.
(similar in meaning)
'if wrong a fellow' is the wordplay.
'wrong' indicates anagramming the letters.
'a fellow' becomes 'ned' (I can't justify this - if you can you should give a lot more credence to this answer).
'if' with letters rearranged gives 'fi'.
'fi'+'ned'='FINED'
'gets' is the link.
Can you help me to learn more?
(Other definitions for fined that I've seen before include "Mulcted" , "Ordered to pay penalty" , "Imposed financial penalty on" , "Fed in (anag.)" .)